Android list view inside a scroll view

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一向
一向 2020-11-21 13:43

I have an android layout which has a scrollView with a number of elements with in it. At the bottom of the scrollView I have a listView

30条回答
  •  南笙
    南笙 (楼主)
    2020-11-21 14:01

    In xml:

    
                    
    

    In Java:

    public class NestedListView extends ListView implements View.OnTouchListener, AbsListView.OnScrollListener {
    
        private int listViewTouchAction;
        private static final int MAXIMUM_LIST_ITEMS_VIEWABLE = 99;
    
        public NestedListView(Context context, AttributeSet attrs) {
            super(context, attrs);
            listViewTouchAction = -1;
            setOnScrollListener(this);
            setOnTouchListener(this);
        }
    
        @Override
        public void onScroll(AbsListView view, int firstVisibleItem,
                             int visibleItemCount, int totalItemCount) {
            if (getAdapter() != null && getAdapter().getCount() > MAXIMUM_LIST_ITEMS_VIEWABLE) {
                if (listViewTouchAction == MotionEvent.ACTION_MOVE) {
                    scrollBy(0, -1);
                }
            }
        }
    
        @Override
        public void onScrollStateChanged(AbsListView view, int scrollState) {
        }
    
        @Override
        protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
            super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    
            int newHeight = 0;
            final int heightMode = MeasureSpec.getMode(heightMeasureSpec);
            int heightSize = MeasureSpec.getSize(heightMeasureSpec);
            if (heightMode != MeasureSpec.EXACTLY) {
                ListAdapter listAdapter = getAdapter();
                if (listAdapter != null && !listAdapter.isEmpty()) {
                    int listPosition = 0;
                    for (listPosition = 0; listPosition < listAdapter.getCount()
                            && listPosition < MAXIMUM_LIST_ITEMS_VIEWABLE; listPosition++) {
                        View listItem = listAdapter.getView(listPosition, null, this);
                        //now it will not throw a NPE if listItem is a ViewGroup instance
                        if (listItem instanceof ViewGroup) {
                            listItem.setLayoutParams(new LayoutParams(
                                    LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
                        }
                        listItem.measure(widthMeasureSpec, heightMeasureSpec);
                        newHeight += listItem.getMeasuredHeight();
                    }
                    newHeight += getDividerHeight() * listPosition;
                }
                if ((heightMode == MeasureSpec.AT_MOST) && (newHeight > heightSize)) {
                    if (newHeight > heightSize) {
                        newHeight = heightSize;
                    }
                }
            } else {
                newHeight = getMeasuredHeight();
            }
            setMeasuredDimension(getMeasuredWidth(), newHeight);
        }
    
        @Override
        public boolean onTouch(View v, MotionEvent event) {
            if (getAdapter() != null && getAdapter().getCount() > MAXIMUM_LIST_ITEMS_VIEWABLE) {
                if (listViewTouchAction == MotionEvent.ACTION_MOVE) {
                    scrollBy(0, 1);
                }
            }
            return false;
        }
    }
    

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